1. Field of the Invention
The present invention relates to a pedal apparatus that is used to operate, for example, brakes of a vehicle, that is variable in anteroposterior position and is high in structural reliability, and that does not change a driver's operation feeling.
2. Description of Related Art
In vehicles, a driver steps on the pedal of a pedal apparatus provided below a dashboard in front of a driving seat to operate, for example, a brake. When starting to drive, the driver adjusts the driving seat to a position at which he/she can easily step on the pedal of the pedal apparatus. However, it is preferable to adjust not only the distance between the driver and the pedal apparatus but also the distance between the driver and each of driving operation apparatuses, such as a steering wheel, to appropriate values, respectively, according to the physical size and preference of the driver. Accordingly, it is desired that the pedal of the pedal apparatus can be changed in the anteroposterior position of the vehicle.
In a case where the pedal of the pedal apparatus used in a braking operation of a vehicle is adapted to be variable in the anteroposterior direction, and where the effect of the driver's stepping force, which is applied to the pedal, on the brake serving as an object to be operated is changed before or after the pedal is moved in the anteroposterior direction of the vehicle, uncomfortable operational feeling is given to the driver. Thus, there has been proposed a mechanism that enables the pedal to move in the anteroposterior direction of the vehicle, and that prevents the effect of the pedal apparatus on the object from being changed.
Both of pedal apparatuses respectively disclosed in European Patent Examined Publication EP 0 256 466 A2 and Japanese Patent Unexamined Publication JP-A-07-334262 are enabled to move a pedal in the anteroposterior direction of a vehicle and to maintain a ratio (hereunder referred to as a “lever ratio”) of a distance between a swing shaft thereof and an application point, such as a brake, to which an operation is applied, to a distance between the swing shaft thereof and the pedal at a substantially constant value by moving a movement member in an up-down direction even when the pedal is moved in the anteroposterior direction of the vehicle.
However, in the case of the pedal apparatus disclosed in EP 0 256 466 A2, the swing shaft of the pedal apparatus is moved in the-up-down direction to maintain the lever ratio at a constant value even when the pedal is moved in the anteroposterior direction of the vehicle. Thus, play for the swing shaft of the pedal apparatus is easily generated. Also, play for the pedal itself is easily generated. Consequently, uncomfortable operational feeling is given to the driver.
Also, in the case of the pedal apparatus disclosed in JP-A-07-334262, a push rod for operating the brake is inclined. Thus, there is a fear of occurrence of a problem of the durability of components, such as a brake master cylinder. Additionally, there is a limitation to the adjustment to the anteroposterior position of the pedal.